| low-pitched(adjective, close, quiet, soft, low) |
| lulled(adjective, silent) |
| mild |
| nonvocal(quiet, soft, low, still, shy) |
| not saying boo(expression, adjective, idiom, close, quiet) |
| not talkative(expression, quiet, low, shy, silent) |
| plumbless |
| plunging |
| quiet speechless(expression, still, hushed) |
| quieted(adjective, close, quiet, soft, low) |
| quieter |
| reserved(adjective, close, quiet, soft, low) |
| reticent(adjective, close, quiet, soft, low) |
| sealed(adjective, calm, quiet, smooth, tranquil) |
| secretive(adjective, close, quiet, soft, low) |
| silentious(still, hushed) |
| smooth(adjective, calm, quiet, tranquil, silent) |
| speechless(adjective, close, quiet, soft, low) |
| stable(adjective, calm, quiet, smooth, tranquil) |
| stagnant(adjective, calm, quiet, smooth, tranquil) |